Most inherited cases of breast cancer are associated with two abnormal genes: BRCA1 (BReast CAncer gene one) and BRCA2 (BReast CAncer gene two). Women with an abnormal BRCA1 or BRCA2 gene have up to an 85% risk of developing breast cancer by age 70. Their risk of ovarian cancer also is higher than average.

Abnormal BRCA1 and BRCA2 genes are found in 5% to 10% of all breast cancer cases in the United States.

One aggressive way to lower the risk of both cancers in women with an abnormal BRCA1 or BRCA2 gene is to remove the ovaries and fallopian tubes. This is called prophylactic (protective) salpingo-oophorectomy (oo-for-EK-tuh-mee).

A study found that removing the ovaries and fallopian tubes of women with an abnormal BRCA1 or BRCA2 gene reduces breast cancer risk by 50% and ovarian cancer by 80%. The researchers combined the results of 10 studies looking at breast and/or ovarian cancer in women with an abnormal BRCA1 or BRCA2 gene.

Removing the ovaries and fallopian tubes to reduce breast cancer risk offers benefits only if the surgery is done before menopause. Removing the ovaries before menopause significantly reduces the level of estrogen in a woman's body. Because some breast cancers require estrogen to grow, removing the ovaries may slow or even stop the growth of breast cancer cells.

Removing the ovaries and fallopian tubes to reduce ovarian cancer risk can be done before or after menopause.

Women with an abnormal BRCA1 or BRCA2 gene often are advised to have their ovaries removed by age 35 or as soon as they're done having children. But this study found that the age at which surgery should be recommended isn't clear because the ages of the women in the studies were all very similar. More research is planned to figure out the best timing for ovary removal surgery, as well as the health consequences of the surgery.

If you learn that you have an abnormal BRCA1 or BRCA2 gene, talk your doctor about ALL of the options that can lower your risk for both breast and ovarian cancer. Removing the ovaries is only one option. Some women may decide to have prophylactic removal of both breasts. There are also medicine options, depending on your menopausal status. Medicines can be used to shutdown the ovaries and hormonal therapies can block estrogen effects or lower estrogen production. Together, you and your doctor can decide on the best risk reduction plan for your unique situation.